(Reuters) - Amazon.com Inc (AMZN.O) may have violated safety measures and labor practices amid the coronavirus pandemic as it fired a warehouse protest leader last month, New York Attorney General Letitia James’s office wrote in a letter to the company last week.

FILE PHOTO: A worker in a face mask walks by trucks parked at an Amazon facility as the global coronavirus outbreak continued in Bethpage on Long Island in New York, U.S., March 17, 2020. REUTERS/Andrew Kelly

“Amazon’s health and safety measures taken in response to the COVID-19 pandemic are so inadequate that they may violate several provisions of the Occupational Safety and Health Act,” James’s office wrote in the letter, whose content was shared by a source familiar with the letter on Monday.

Amazon terminated Christian Smalls, a critic of the company’s warehouse conditions in the pandemic, on grounds that he put others at risk by violating his paid quarantine when he joined a demonstration at Amazon’s Staten Island, New York, fulfillment center.

The letter, sent to the company on April 22, adds that preliminary findings “raise serious concern that Amazon may have discharged (Smalls) in order to silence his complaints and send a threatening message to other employees that they should also keep quiet about any health and safety concerns.”

In response, Amazon spokeswoman Rachael Lighty said the e-commerce company did not terminate Smalls’ employment for organizing a 15-person protest but because he put the health and safety of others at risk, adding that he also received numerous warnings for violating social distancing guidelines.

“He was also found to have had close contact with a diagnosed associate with a confirmed case of COVID-19 and was asked to remain home with pay for 14-days. Despite that instruction to stay home with pay, he came onsite further putting the teams at risk,” Lighty said.

The letter, first reported by NPR, also called on the e-commerce giant to close some warehouses for “adequate sanitization and disinfection”.

“We encourage anyone interested in the facts to compare our overall pay and benefits, as well as our speed in managing this crisis, to other retailers and major employers across the country,” Amazon’s Lighty said.

The world’s largest online retailer has been facing intense scrutiny by lawmakers and unions over whether it is doing enough to protect staff from the novel coronavirus.

In March, New York City Mayor Bill de Blasio said he ordered the city’s human rights commission to open an investigation into the dismissal of Smalls.

Reporting by Kanishka Singh and Aakriti Bhalla in Bengaluru, additional reporting by Akanksha Rana in Bengaluru; Editing by Saumyadeb Chakrabarty